QUALITY CHARACTERISTICS AND ANTIOXIDANT ACTIVITY OF STIRRED YOGHURT FORTIFIED WITH DESERT TRUFFLE

Abstract

Different kinds of natural food ingredients could be in making yoghurt to produce palatable and more healthy fermented milk. Desert truffle is a popular nutritious food that showed a work was to produce healthy yoghurt supplemented with dessert truffle powder (DTP). Stirred yoghurt was prepared from cow’s milk standardized to 3% fat and supplemented with dried DTP at levels of 1, 3 and 5% prior to inoculation with yoghurt culture. Resultant stirred yoghurt was analyzed when fresh and after 3, 6, and 9 days of the cold storage. Chemical composition of yoghurt milk showed an increased protein and total solids contents. Stirred yoghurt with DTP showed a reduction in both apparent viscosity as well as syneresis during storage period. Sensory evaluation revealed that 1% DTP is the most acceptable stirred yoghurt compared to 3 and 5% DTP treatments. There was a correlation between content of phenolic compounds in stirred yoghurt and both quantity of DTP and antioxidant activity. In sum, a healthy stirred yoghurt can be produced by addition of DTP which increased content of phenolic compounds and antioxidant activity of the stirred yoghurt. The highest sensory scores were accounted for 1% DTP.